#nav_home {
  display: none;
}

#nav {
  z-index: 10;
}

#nav li a:hover {
  background-position: 0 -42px;
}

#nb_0 {
  width: 51px;
  height: 42px;
  background: url("/images/assembly/nav_home.gif") no-repeat;
  text-indent: -999em;
  overflow: hidden;
}

#nb_1 {
  width: 91px;
  height: 42px;
  background: url("/images/assembly/nav_about.gif") no-repeat;
  text-indent: -999em;
  overflow: hidden;
}


#nb_2 {
  width: 121px;
  height: 42px;
  background: url("/images/assembly/nav_explore.gif") no-repeat;
  text-indent: -999em;
  overflow: hidden;
}

#nb_3 {
  width: 106px;
  height: 42px;
  background: url("/images/assembly/nav_protected.gif") no-repeat;
  text-indent: -999em;
  overflow: hidden;
}

#nb_4 {
  width: 138px;
  height: 42px;
  background: url("/images/assembly/nav_preserve.gif") no-repeat;
  text-indent: -999em;
  overflow: hidden;
}

#nb_5 {
  width: 80px;
  height: 42px;
  background: url("/images/assembly/nav_resources.gif") no-repeat;
  text-indent: -999em;
  overflow: hidden;
}